What is the loop order of bmesh faces?
From http://wiki.blender.org/index.php/Dev:2.6/Source/Modeling/BMesh/Design:


  Loops store several handy pointers:
  
  
  v - pointer to the vertex at the start of the edge (where "start" is defined by CCW order)
  


this means that CCW indexing can be assumed if I don't get it wrong. Also note that the loop-list on the face is circular according to this:


  Faces link to a loop in the loop cycle, the circular linked list of loops defining the boundary of the face.